Diesel bug

[Alcyone]

I just thought I'd jot down a few notes on my recent experience with this for the record. I'm not really interested in arguing the pros and cons, if anyone finds this useful, great, if not, no probs.

I changed the engine in our Cobra 850 last October, fitting a new Beta 20HP. The tank was a Plastimo 45 l tank, about 18 months old. We fill with red diesel from jerry cans. Over the winter, our tank was less than half full.

On our first 'outing' of the year, after sea trials, our engine stopped near Portishead. We were lucky enough to be towed to the marina by a friend. One of the diesel pipes was blocked by a small black lump which I took to be a piece of broken pipe, probably wrongly.

We then had approx 10 hours of trouble free engine use before I again broke down, this time in a foul tide West of Skomer island, Pembs. I sailed back to our mooring in Dale.

The following day, I found the primary filter blocked with black slime, and several pipes in the same state. I cleaned them all out and suspected the diesel bug, realising that our Portishead problem was probably an early warning that I'd overlooked.

I bought some diesel treatment, called 'Marine 16' from a local Chandlers. They had a photocopy of a YBW article claiming good results with this treatment. It also claimed to dissolve any slime left in the tank - I didn't believe this. I administered the 'knockout dose' of around 20ml for the 20l diesel left in the tank. Left it a week.

This weekend just past, I removed the tank inspection plate and scraped around in the tank, including several 'scrapes' of the bottom of the tank. I could find no sign of any slime whatsoever. Gone. Completely clean. I poured diesel from the tank into a 2l plastic bottle. No black bits or solids whatsoever.

Engine runs fine and filters are clear.

Not an in depth scientific analysis, I agree, but it certainly seems that the claims made about this treatment appear to have been true, in this case.

 

[stuhaynes]

I just thought I'd jot down a few notes on my recent experience with this for the record. I'm not really interested in arguing the pros and cons, if anyone finds this useful, great, if not, no probs.

I changed the engine in our Cobra 850 last October, fitting a new Beta 20HP. The tank was a Plastimo 45 l tank, about 18 months old. We fill with red diesel from jerry cans. Over the winter, our tank was less than half full.

On our first 'outing' of the year, after sea trials, our engine stopped near Portishead. We were lucky enough to be towed to the marina by a friend. One of the diesel pipes was blocked by a small black lump which I took to be a piece of broken pipe, probably wrongly.

We then had approx 10 hours of trouble free engine use before I again broke down, this time in a foul tide West of Skomer island, Pembs. I sailed back to our mooring in Dale.

The following day, I found the primary filter blocked with black slime, and several pipes in the same state. I cleaned them all out and suspected the diesel bug, realising that our Portishead problem was probably an early warning that I'd overlooked.

I bought some diesel treatment, called 'Marine 16' from a local Chandlers. They had a photocopy of a YBW article claiming good results with this treatment. It also claimed to dissolve any slime left in the tank - I didn't believe this. I administered the 'knockout dose' of around 20ml for the 20l diesel left in the tank. Left it a week.

This weekend just past, I removed the tank inspection plate and scraped around in the tank, including several 'scrapes' of the bottom of the tank. I could find no sign of any slime whatsoever. Gone. Completely clean. I poured diesel from the tank into a 2l plastic bottle. No black bits or solids whatsoever.

Engine runs fine and filters are clear.

Not an in depth scientific analysis, I agree, but it certainly seems that the claims made about this treatment appear to have been true, in this case.

I read the PBO report on this and ordered a bottle of Marine 16. I've not used it yet because I want to clean the tanks first. I used a sump pump to suck out the bottom of the tank and the resulting 'sample' was disgusting. After 3 weeks settling in a plastic bottle we have about an inch of water, and inch of settled **** and the remainder? A brownish liquid that has not settled at all!

I'm looking for someone in the Doncaster area who needs their own tanks cleaning. The cost for my boat alone is around £200, but I can get 2 boats done for £150 each. I've probably got £100 of fuel in the tanks which I will be able to re-use as opposed to dumping the lot. Anyone reading this in the Donny area that is interested, PM me, save us both some money.

My intention, after getting the tanks cleaned is to 'shock' dose the cleaned fuel and add another 100 litres. I've also bought a Perkins water trap and a twin CAV type fuel filter. I'm going to try to replace the original (felt) filter with a more modern type. This because the engine is 60 years old and parts not available.

Fingers crossed! It is however, nice to get some first hand feedback about Marine 16. Thanks for posting.

 

[GAJ]

I thought Fuel Set just emulsified the water and kept in in suspension therefore sending it through the injector pump and injectors which could cause corrosion or other issues?
Whereas Marine 16 and others drops the water to the bottom of the tank to be drained off and removed from the system. A better solution I would think?

 

[lancelot]

Diesel Bug

I just thought I'd jot down a few notes on my recent experience with this for the record. I'm not really interested in arguing the pros and cons, if anyone finds this useful, great, if not, no probs.

I changed the engine in our Cobra 850 last October, fitting a new Beta 20HP. The tank was a Plastimo 45 l tank, about 18 months old. We fill with red diesel from jerry cans. Over the winter, our tank was less than half full.

On our first 'outing' of the year, after sea trials, our engine stopped near Portishead. We were lucky enough to be towed to the marina by a friend. One of the diesel pipes was blocked by a small black lump which I took to be a piece of broken pipe, probably wrongly.

We then had approx 10 hours of trouble free engine use before I again broke down, this time in a foul tide West of Skomer island, Pembs. I sailed back to our mooring in Dale.

The following day, I found the primary filter blocked with black slime, and several pipes in the same state. I cleaned them all out and suspected the diesel bug, realising that our Portishead problem was probably an early warning that I'd overlooked.

I bought some diesel treatment, called 'Marine 16' from a local Chandlers. They had a photocopy of a YBW article claiming good results with this treatment. It also claimed to dissolve any slime left in the tank - I didn't believe this. I administered the 'knockout dose' of around 20ml for the 20l diesel left in the tank. Left it a week.

This weekend just past, I removed the tank inspection plate and scraped around in the tank, including several 'scrapes' of the bottom of the tank. I could find no sign of any slime whatsoever. Gone. Completely clean. I poured diesel from the tank into a 2l plastic bottle. No black bits or solids whatsoever.

Engine runs fine and filters are clear.

Not an in depth scientific analysis, I agree, but it certainly seems that the claims made about this treatment appear to have been true, in this case.

Hi Martin,
It is good to read your report regarding the bug and Marine 16.
Do you know if the bug is residue from previous engine or is it a result of using the new biodiesel?
I have a Cobra 850, Swanea based, however, I have three quarters of the tank from old red diesel with Marine 16 in it. I must admit I am worried about refilling with the new type diesel in case of blocked filters etc. It will not be long before I need to fill. Do you think I will have the same problems, it amazes me how quickly you had a problem in view of the new tank?
Many thanks for letting us know about the bug problem.
Fair winds,
Lancelot

 

[Alcyone]

Hi Martin,
It is good to read your report regarding the bug and Marine 16.
Do you know if the bug is residue from previous engine or is it a result of using the new biodiesel?
I have a Cobra 850, Swanea based, however, I have three quarters of the tank from old red diesel with Marine 16 in it. I must admit I am worried about refilling with the new type diesel in case of blocked filters etc. It will not be long before I need to fill. Do you think I will have the same problems, it amazes me how quickly you had a problem in view of the new tank?
Many thanks for letting us know about the bug problem.
Fair winds,
Lancelot

I generally have a policy of keeping the diesel tank and the jerry cans full. Not through any knowledge of the diesel bug, I should add, just keep the boat as ready as possible - you never know when a chance to go somewhere will pop up.

With the engine change last winter, I neglected this, and I think it was the half empty tanks that led to condensation that was the root cause. Early in the year, with temperatures cold, there was little growth, but as the temperature warmed up in the dry spring, I think it started growing and that was that.

The way the treatment dealt with the problem, I wouldn't worry. I will dose ours at preventative dose from now on, which is 2ml per tank - one bottle will last 50 tanks!

I think I probably will check the tank during winter maintenance, drain any water, but I am so pleased with the treatment, I am quite relaxed about it at the moment. I guess bug resistance may become a problem, but we shall see.

Still hoping to see you at some point, but we're in Dale until Sept/Oct.

 

[lancelot]

I generally have a policy of keeping the diesel tank and the jerry cans full. Not through any knowledge of the diesel bug, I should add, just keep the boat as ready as possible - you never know when a chance to go somewhere will pop up.

With the engine change last winter, I neglected this, and I think it was the half empty tanks that led to condensation that was the root cause. Early in the year, with temperatures cold, there was little growth, but as the temperature warmed up in the dry spring, I think it started growing and that was that.

The way the treatment dealt with the problem, I wouldn't worry. I will dose ours at preventative dose from now on, which is 2ml per tank - one bottle will last 50 tanks!

I think I probably will check the tank during winter maintenance, drain any water, but I am so pleased with the treatment, I am quite relaxed about it at the moment. I guess bug resistance may become a problem, but we shall see.

Still hoping to see you at some point, but we're in Dale until Sept/Oct.

Cheers Martin
I filled the tank just before the winter and added a large amount of Marine 16. I have probably overdosed on the stuff - in fact I will possibly get 2 to 3 dosings out of mine (small bottle).
I do feel more confident now.
Yes, I will look out for you. Give us a shout if you pop into Swansea.
Fair winds
Keith

 

[SimbaDog]

Was it the diesel fuel complete you used? They seem to do a few variants

 

[Alcyone]

Nope, it was the diesel bug treatment:

4th one down here,

http://www.marine16.co.uk/acatalog/Fuel_Treatment_Products.html

Although it cost me 8 quid odd.

 

[sparetime]

types od f diesel and bug

There is now a variety of fuels in the market. The one giving most concern is biodiesel. This uses fatty acid methyl ester (FAME). This can be made from a variety of sources such as palm oil, rape oil, vegetable oil etc. The problem with FAME is that it appears to hold in moisture to the body of the fuel. It is recommended that biodiesel is not stored for more tham 6 months. I have a quote from a fuel consultant saying that in the worst case in a marine environment "you can have 30% unusable fuel in your tanks in 6 weeks if you do not use an additive".

If you use Fuel Set or other enzyme based products, especially where they use glycol to remove water the water is held in even more. leave it for a while and the organisms grow like mad, especially in warm weather. By dropping out the water the water fuel inteface is only the size of the area of your tank. Use a bug preventer and no problems. If there is glycol it adds to the water content within the fuel. Great when thr fuel is paasing through the system but when you leave it the surface area created by the FAME, glycol, water, fuel micelles is millions of times greater and hence the rapid bug growth. Enzymes themselves are not killing bugs or they would be labelled as a biocide.

If this high water and fuel is left in your pump then of course there is potential for corrosion and this can be seen in the brown colour of contaminatiton when you clean the system out.

Fuel also makes its way down into your crankcase where high water content causes emulsion formation and corrosion. The fuel treatment must also be compatible with the lubricating oil that you use.

High water content in fuel also gives the chance of water dropping out under the high pressures used these days in diesel engine pumps and causing injector plugging.

If you have a common rail diesel then the high temperature of the returning fuel has to be considered when choosing the suitability of an additive.

Add to this the loss on lubrication caused by ulsd and the problems increase. I would not choose water as my preferred engine lubricant.

As for fuels if you use road diesel there can be 7% FAME in it without a change in labelling. If you are on inland waterways you have to use the same fuel as the road users, it will contain FAME. Marinas vary. Some are using biodiesel and some are managing to get marine diesel which is FAME free and higher sulphur. This is unlilkely to last. Some marina suppliers are using additives but others are wary as if anything goes wrong with your engine they could be liable. Ask the operator what they are giving you.

My advice is use an additive, choose one that is well proven and does everything. My yacht engine failed to start in light airs off Lands End. It isn't funny. It was my niece standing on the fuel cut off at the end of her bunk that caused it but is was certainly worrying.

 

[Tintin]

I've had ongoing problems so late last year treated the tanks (after fuel polishing) to a large dose of Marine 16, the topped the tanks up for the winter.

First thing this season I drew a fuelk sample off, and while the bug had gone there was a fair bit of water in suspension so I got some Fuel Set and added that as it emulsifies the water.

So far so good........

 

[sparetime]

diesel bug

This is the problem with different types of fuels and treatments. Marine 16 make several. The Diesel Bug Treatment is a clear liquid that just prevents or kills bug according to dose. They also make Diesel Fuel Complete that combats everyting for all diesel engines and all fuel types.

If you can see water haze in fuel then adding a glycol/enzyme will make it look worse as it emulsifies water into the fuel to takes it through your engine. This is what they say prevents bug growth as the water is removed. This is only so if the fuel is used up and not left in the tank. I still do not like the idea of using water as an engine lubricant.

The Diesel Fuel Complete drops the water out and prevents bug growth so ensuring no water is left in the fuel. It contains cleaners to reduce fuel system deposits to zero.

Any biocide that you use including the bug treatment from Marine 16 will kill the enzymes in enzyme/glycol products. This includes biocides that may have been added by the fuel suppliers anywhere in the distribution chain that you may not be aware of.

There are around 40 bugs that can grow in fuel. One at least does not require the oxygen from water and occurs in stagnant zones and in bilges sometimes. if this is present the fuel or bilges smell of rotten eggs and the resultant by-product is sulphuric acid that has been known to eat through half inch steel plate.

 

[SimbaDog]

There seems to be a lot of confusing & conflicting information on diesel & treatments
Have to say that the Marine 16 diesel fuel complete looks like a good idea, has anyone here used it?

 

[GAJ]

The water will drop to the bottom of the tank if you use nothing, its what water does in oil. The problem is that the dreaded bug then grows in the diesel/water interface. Fuel set treats the water into the diesel removing the bugs life support system. Now used it for over 15 years and no corrosion issues, would have thought half a tank of water would have produced a problem. But yes we did remove as much water as possible before doseing the fuel.

this is what Liquid Engineering (Makers of Fuelset) say on the subject:

"
Emulsified Fuel
Water emulsion or water held in suspension can cause serious damage to fuel system components. The water content causes loss of lubrication resulting in worn fuel pumps and injectors.



Emulsified water also reacts with chemicals in the fuel at the point of combustion, which causes contaminates such as gum, wax and resin to separate and foul fuel systems, especially injectors. Emulsified water can seriously degrade certain types of fuel filters.



A water emulsion, left untreated eventually separates from the fuel and provides an environment for the 'diesel bug' .



Fuel Set chemically bonds emulsified or free water into the fuel. This eliminates the harmful effects of water in fuel systems. Having water as part of the fuels’ make-up lowers smoke and nitrous oxide emissions.
"

so it seems it dosent emulsify the water.

Oooops I got it wrong then. Just being a boaty person and not a chemist I was led by what I was told by our local friendly marina when I enquired about the type of diesel they are selling and what to do about it. Hey I only said I thought it emulsified the water...............it does not have any lubrication in it though does it?

Still learning about this stuff

Anyway what I was more concerened about was the lack of lubrication and short storage life of the biodiesel which according to the powers that be can be a problem as I am sure that the bug killers all work to a greater or lesser degree. So I looked for a product that could do the lot in one go, kill the bug, lubricate the pump and extend the storage life in the tank. We have 350lt of diesel in our tank and the thought of it going off over the winter really upsets me.

I opted for Marine 16 Diesel Fuel Complete after the mags said it was good and the RNLI use it, apparently it does do all the things above and more, perhaps there is another product out there that is a one hit wonder as well it's just I have yet to find it.

It all started with some little black bits in the fuel line/filters and cloudy looking fuel, and me fretting about blocked filters and lee shores and all that. Put this stuff in and so far no more black bits and clear looking diesel. We shall see what happens after the winter if the juice still has the same bang or there is a load of gunge in the tank.
All a bit tricky really.

 

[xyachtdave]

There seems to be a lot of confusing & conflicting information on diesel & treatments
Have to say that the Marine 16 diesel fuel complete looks like a good idea, has anyone here used it?

I am having problems with diesel bug, despite using 'fuel set' in white road diesel. sailing boat so not much turnover of fuel.

i read through this and have today administered a full on dose of the bug killer, plus the treatment and the other one they do.

Will let you know....

 

[PabloPicasso]

I used marine 16 on my boat wioth excellent results after real nightmarish and persistant problems. Everything has been fine since.

 

[jimi]

A tip I was give by a scientist in the marine fuel lab in Hamburg was to add a small amount of petrol to diesel ( 5% occasionally). The lead replacement stuff is allegedly toxic to the bug.

 

[Spyro]

A tip I was give by a scientist in the marine fuel lab in Hamburg was to add a small amount of petrol to diesel ( 5% occasionally). The lead replacement stuff is allegedly toxic to the bug.

5% occasionally doesn't sound very scientific. If my tank is empty and I fill up with 5% petrol that means my tank will be 5% petrol. Is it wise to run my engine on that?

 

[xyachtdave]

Forgot to mention the marine 16 was evil stuff with most of the label taken over with health and safety warnings.

I am not expecting much to live in the tank from now on!

 

[jimi]

5% occasionally doesn't sound very scientific. If my tank is empty and I fill up with 5% petrol that means my tank will be 5% petrol. Is it wise to run my engine on that?

5% of petrol to diesel usually means that the petrol content is 5% of the diesel content.
if you fill 5% of an empty tank's volume with petrol ,, that means that the % of petrol to diesel ratio is infinite. However I suspect you knew that already.
If not, I hope it helps.